Manufacture of varnish.



UNITED STATES PATENT OFFICE.

RUDOLF WEEBER, 0F BARN, AUSTRIA.

MANUFACTURE or VARNISH.

Specification of Letters Patent.

No Drawing.

the purpose of the covering varnish made from linseed oil, and therefore can be used for the manufacture of oil cloth and lino leum.

To that end, it has been suggested to treat oils by heating them in a vacuum, or with superheated steam or inert or neutral gases, in order to remove injurious ingredients. recesses have the drawback'however that t ey do not remove'completely all the free fatty acids, as in these circumstances the latter undergo further decomposition and conversion. In any case, these processes either considerably reduce the yield of varnish, or yield an inferior badly drying varnish.

A process is known in the manufacture of varnish from linseed oil, in which a small quantity of alkalis, carbonates of alkalis or alkaline earths (more particularly lime) are added to heated fatty oils. These additions are admissible only in a maximum quantity of-%% of the quantity of oil, as a. larger addition stops polymerization and completely 'does away with the drying qua-l1ty of the varnish obtained. For that reason the admissible quantity in the known process is given as H%. V

Semi-drying oils, such as train oils, containhowever from 15-20% and frequently even 30% offree fatty acids. If semi-drying oils, more particularly train oils, were treated by the process suggested for fatty oils, and the necessary quantity of alkalis added to the train oils during the process of boiling, polymerization would be prevented, and the drying .or siccative property of the varnish obtained, would be destroyed as the soaps lime or alkalinesoaps formed counteract the said properties. The addition of larger quantities of alkalis during the boiling process would moreover bring about an extensive saponification-and hy-,

drolysis of the train oils.

The said drawbacks are obviated by the process according to this invention as regards oil cloth and linoleum manufacture. This is attained by the fact that the free fatty acids which are saponified by the addition of a lye are separated from the oil before the boiling process, so that only pure oil is boiled. The oils are first treated in a cold or moderately heated state with soda or lime or lye of suitable concentration, whereupon the soap thus formed is allowed to settle from the free fatty acids and alkali hydrate, and is decanted or separated in some other Way from the pure oil. The said pure oil consisting only of the fatty acids originally combined, and separated above the soap, is then submitted to a boilmg process as for varnish manufacture,

preferably at the same time being polymerized in the known manner or boiled with or without siccatives. Before the boiling, an traces of suspended alkali particles which cannot be completely removed from the oil, can be neutralized by a little acid.

The above process .is intended for all kinds of train-oil, (fish-oil) that are of a glyceridic character, as well as for such that chiefly consist of compound ethers of or containing monohydric alcohols, the glycerids being hydrolized in the process through the combination of bases and the hydrolized acids subsequently treated.

As an example of the execution of the process the following is given:

Dark-brown train-oil or fish oil, is primarily mixed with soda-lye and a itated, and the mixture is left undisturbed or two days at an approximate temperature of 65 C. until the produced soap has settled at Patented Feb. 26, 1918. Application filed February 19, 1914. Serial No. 819,756.

the bottom. The dpure oil that collects'at the top is skimme out, and is, for example, boiled down for seven hours at' a tempera ture of 300 C. with a siccative cobalt. A part of the thus obtained mass is set upon a wax-layer or foundation, and dries in about seven hours upon being s bj i d tem erature of 75 C. aving now particularly d ribed and ascertained thenaturc of my said invention and in-wh'at manner the same is to be performed, I declare that What I claim is.

1. The process for the maufacture of varnish from semi-drying oils, such as train- 110 3. The process for the manufacture of yarnish from semi-drying oils, such. as train-oil, which consists nilrvating lhgyoil with a lyo to sa ionify the 'l'rvv fatty auhl, separating the soap thus formed from tho oil, and polymerizing the oil with siccativos until varnish is prmluood.

In testimony whereof I havo Sign name to the foregoing specification in the presenuu of two sul'lsurihing \Vltl'lGSSlS.

RU DOL l? W E EBl-GR.

\ViLnr-sses:

AUGUST Fuoonln GUSTAV WOLFE. 

